<?php
/**
* @version $Id: strspn.php 10381 2008-06-01 03:35:53Z pasamio $
* @package utf8
* @subpackage strings
*/

//---------------------------------------------------------------
/**
* UTF-8 aware alternative to strspn
* Find length of initial segment matching mask
* Note: requires utf8_strlen and utf8_substr (if start, length are used)
* @param string
* @return int
* @see http://www.php.net/strspn
* @package utf8
* @subpackage strings
*/
function utf8_strspn($str, $mask, $start = NULL, $length = NULL) {

	$mask = preg_replace('!([\\\\\\-\\]\\[/^])!','\\\${1}',$mask);

	if ( $start !== NULL || $length !== NULL ) {
		$str = utf8_substr($str, $start, $length);
	}

	preg_match('/^['.$mask.']+/u',$str, $matches);

	if ( isset($matches[0]) ) {
		return utf8_strlen($matches[0]);
	}

	return 0;

}

